Plymouth Devils failed to build on Friday's home win over Scunthorpe by losing heavily at Mildenhall on Sunday.
Mildenhall dominated the tie, winning 12 of the 15 heats, with Jerran Hart leading the way on 15 points from his five rides.
Barrie Evans scored 13 points for the home side, while reserve Joe Jacobs contributed an impressive 11.
Mark Simmonds was the only Devils rider to break into double figures, finishing the tie with 11 points from five rides.
Plymouth had gone into the tie on the back of an impressive 59-33 win over Scunthorpe at the St Boniface Arena on Friday night.
A 15-point maximum from Paul Starke was the highlight, while skipper Seemond Stephens scored 13 points from his five rides.
The weekend's results mean the Devils are now eighth in the National League standings, with six points from their first four matches.